Chemical vapor infiltration and deposition (CVI/CVD) is a known process for making composite structures such as carbon/carbon brake disks. The CVI/CVD process typically used for making carbon/carbon brake disks is sometimes referred to as “conventional” or “isothermal” CVI/CVD. This process involves passing a reactant gas or gas mixture around heated stack of porous structures (e.g., a carbonized stack of porous structures) at absolute pressures as low as a few torr (˜400 Pa or less). The gas diffuses into the stack of porous materials, driven by concentration gradients, and undergoes a CVD reaction such as thermal decomposition, hydrogen reduction, co-reduction, oxidation, carbidization, or nitridation to deposit a binding matrix.
Depending on CVI/CVD methodology and conditions, the porous structure may not densify at a uniform rate across the thickness of a porous structure, may not form a desired microstructure and/or may be associated with long processing times. Thus, creation of uniformly densified porous structures may be impaired using conventional systems and methods.